 You've heard of masks being used for Halloween and by superheroes like Batman. But how about by environmentalists intent on curbing global warming? Well, believe it or not, such a mask called the green screen has been developed by designer Robert Ortega. And it promises to both keep your lungs safe from the world as well as protect the earth from the carbon dioxide you breathe out. The mask, as you might guess, is made from all natural materials. It is crafted with wood pulp and embedded with seeds that actually sprout while you're wearing it.